Bird flu has led to a wide variety of symptoms during recent outbreaks, including common flu symptoms like cough and vomiting. Many have also had conjunctivitis or pink eye as their only symptom, which experts suspect is from contaminated milk from cows infected by bird flu being splashed onto workers.

Since the summer, the U.S. has begun preparing about 10 million doses of a vaccine that they think will be effective against H5N1 bird flu. Federal officials have elected not to u